Mature cells can be reprogrammed to become pluripotent

The 2012 Nobel Prize in Physiology or Medicine was awarded to John Gurdon and Shinya Yamanaka for their work towards the development of stem cells from specialised mature cells. Stem cells are of great interest in medical research because they can form into nearly any type of cell in the body.

John Gurdon was noted for his work in 1962 when he successfully cloned a frog. By taking the nucleus from a cell in the intestine of a tadpole and placing it in an egg cell, it developed into a fully functional tadpole. Not only was this a tremendous achievement, it also provided the definitive proof that a specialised cell in the body still contained all of the genetic material required to produce the entire organism. This launched the field of cloning, which has had notable successes since with Dolly the sheep and recently the cloning of a human skin cell to extract embryonic stem cells.

Shinya Yamanaka’s breakthrough came over 40 years later. By studying stem cells produced in embryos, he found a set of genes that could be introduced into a mouse skin cell that would reprogram it to become like an embryonic stem cell. This means that a cell could be taken from a patient, be reprogrammed and be converted into another type of cell, such as a nerve cell. Until the recent development in human cell cloning, this was the only method of producing genetically identical stem cells that could be used for future stem cell therapies.